You can get into cnc the diy route for between ~$2k and ~$8k depending on the amount of rigidity you want. There are conversation kits available for common import mills to make the process relatively easy but the control and wiring isn't for the faint of heart.

I built one out of a PM-833TV and it's taken years to get working well, and I probably should have just bought a used HAAS at this point, but if you build it You Will Learn one way or another.

Words of wisdom I wish I'd had: spend the money on decent over specced servos with ethercat. Don't skimp or you'll end up having to just redo stuff and it'll cost a lot of money. Do not buy stepper motors period.